title: Pretreatment 25-hydroxyvitamin D levels and durability of anti-tumor necrosis factor-α therapy in inflammatory bowel diseases.
abstract: BACKGROUND
  Emerging evidence supports an immunologic role for 25-hydroxyvitamin D (25(OH)D) in inflammatory bowel disease (IBD). Here we examined if pretreatment vitamin D status influences durability of anti-tumor necrosis factor (TNF)-α therapy in patients with Crohn's disease (CD) or ulcerative colitis (UC).
  
  
  METHODS
  All IBD patients who had plasma 25(OH)D level checked <3 months prior to initiating anti-TNF-α therapy were included in this retrospective single-center cohort study. Our main predictor variable was insufficient plasma 25(OH)D (<30 ng/mL). Cox proportional hazards model adjusting for potential confounders was used to identify the independent effect of pretreatment vitamin D on biologic treatment cessation.
  
  
  RESULTS
  Our study included 101 IBD patients (74 CD; median disease duration 9 years). The median index 25(OH)D level was 27 ng/mL (interquartile range, 20-33 ng/mL). One-third of the patients had prior exposure to anti-TNF-α therapy. On multivariate analysis, patients with insufficient vitamin D demonstrated earlier cessation of anti-TNF-α therapy (hazard ratio [HR], 2.13; 95% confidence interval [CI], 1.03-4.39; P = .04). This effect was significant in patients who stopped treatment for loss of response (HR, 3.49; 95% CI, 1.34-9.09) and stronger for CD (HR, 2.38; 95% CI, 0.95-5.99) than UC (P = NS).
  
  
  CONCLUSIONS
  Our findings suggest that vitamin D levels may influence durability of anti-TNF-α induction and maintenance therapy. Larger cohort studies and clinical trials of supplemental vitamin D use with disease activity as an end point may be warranted.
authors.affiliation: Department of Medicine, Massachusetts General Hospital, Boston.
authors.forename: Zachary A
authors.initials: ZA
authors.lastname: Zator
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Cantu
authors.forename: Gauree Gupta
authors.initials: GG
authors.lastname: Konijeti
authors.forename: Deanna D
authors.initials: DD
authors.lastname: Nguyen
authors.forename: Jenny
authors.initials: J
authors.lastname: Sauk
authors.forename: Vijay
authors.initials: V
authors.lastname: Yajnik
authors.forename: Ashwin N
authors.initials: AN
authors.lastname: Ananthakrishnan
mesh_terms: D000293:Adolescent; D000328:Adult; D019587:Dietary Supplements; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000097:blood / Q000150:complications / Q000188:drug therapy*; D008297:Male; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications; D055815:Young Adult
chemical_list: D014409:Tumor Necrosis Factor-alpha; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: Crohn’s disease; biologic therapy; ulcerative colitis; vitamin D